In most of portable electronic apparatus such as cellular phones or personal digital assistants (PDAs), planar displays are used for revealing various operational information. Please refer to FIG. 1 which is a circuit block diagram illustrating a conventional display control device for controlling a liquid crystal display of a portable electronic apparatus. The control device is electrically connected to a main controller 10 and a liquid crystal panel 13 of the portable electronic apparatus, and includes a gamma adjuster 11, a digital-to-analog converter (DAC) 12, and a timing controller 14. The main controller 10, e.g. a central processing unit (CPU) or a digital signal processor (DSP), outputs a digital data display signal and a control signal to the timing controller of the display control device. The digital data display signal is adjusted to comply with an optoelectronic response feature of the liquid crystal display by the gamma adjuster 11 and then converted into an analog data display signal by the DAC 12. Subsequently, the analog data is outputted to the liquid crystal panel 13. In the meantime, a set of panel display control signals required by the liquid crystal panel 13 for display is generated by the timing controller 14 in response to the control signal.
As is understood by those who are familiar with the display operation principle, the most popular way, so far, to refresh frames is to quickly refresh each pixel data of every scan line according to the analog data display signal in response to the panel display control signals. The main controller 10, however, needs to continuously output digital data display signals and assets control signals, resulting in large power consumption and thus shortened standby time.
Therefore, the purpose of the present invention is to develop a device and a method for controlling a display of a portable electronic apparatus to deal with the above situations encountered in the prior art.